Police in Lebanon are seeking 700 (out of 100,000 who arrived this Summer) tourists from the Persian Gulf, who apparently did not return home. It is believed that many of the missing are Islamic terrorists.
The Taiwanese need to take notice of this, in case the number of missing mainland tourists suddently spikes up.
It will be much more convenient for the PLA if they can send even just their special forces into Taiwan before H-Hour on tourist visas rather than sending them in on parachutes and small rubber boats. Imagine how many infiltrators out of much larger tourist traffic to Taiwan there could be? You could conceivably get your special forces types plus several battalions of elite light infantry (think Rangers) positioned this way.
Much depends on how quickly Taiwanese authorities become aware of tourists who fail to return to China and whether the Taiwanese want to publicly make an issue of it--and wreck so-called improving relations--by calling out the dogs to find them. One thing for sure, the Chinese couldn't keep too many in place for long, so if there is a spike in lost tourists, the Taiwanese would be wise to moblize immediately.